export const a = function(){
    var can = document.getElementById('canvas');
    var ctx = can.getContext('2d');
    var w = can.width = window.innerWidth;
    var h = can.height = window.innerHeight;

    var count = 10;
    var drops = [];
    window.οnresize = function () {
    w = can.width = window.innerWidth;
    h = can.height = window.innerHeight;
    };

    function Drop() {}
    Drop.prototype = {
    init: function () {
        this.x = random(0, w);
        this.y = 0;
        this.r = 1;
        this.color = '#0ff';
        this.vy = random(4, 5);
        this.vr = 1;
        this.a = 1;
        this.va = 0.96;
        this.l = random(h * 0.8, h * 0.9);
    },
    draw: function () {
        if (this.y > this.l) {
        ctx.beginPath();
        ctx.arc(this.x, this.y, this.r, 0, 2 * Math.PI, false);
        ctx.strokeStyle = 'rgba(0,255,255,' + this.a + ')';
        ctx.stroke();
        } else {
        ctx.fillStyle = color(this.a);
        ctx.fillRect(this.x, this.y, 2, 10);
        }
        this.update();
    },
    update: function () {
        if (this.y < this.l) {
        this.y += this.vy;
        } else {
        if (this.a > 0.03) {
            this.r += this.vr;
            if (this.r > 50) {
            this.a *= this.va;
            }
        } else {
            this.init();
        }
        }
    }
    }

    function move() {
    ctx.fillStyle = 'rgba(0,0,0,.1)';
    ctx.fillRect(0, 0, w, h);
    for (var i = 0; i < drops.length; i++) {
        drops[i].draw();
    }
    requestAnimationFrame(move);
    };

    function setup() {
    for (var i = 0; i < count; i++) {
        (function (j) {
        setTimeout(function () {
            var drop = new Drop();
            drop.init();
            drops.push(drop);
        }, j * 200);
        }(i))
    }
    };
    setup();
    move();

    function random(min, max) {
    return Math.random() * (max - min) + min;
    };

    function color(a) {
    // var r = Math.floor(Math.random() * 255);
    // var g = Math.floor(Math.random() * 255);
    // var b = Math.floor(Math.random() * 255);
    // return 'rgba(' + r + ',' + g + ',' + b + ',' + a + ')';
    return 'rgba(255,255,255,'+ a +')'
    };
}